1. Field of the Invention
Resistance spot welds are required to be of sufficient size to meet the design expectations for the parts. Based primarily on automotive requirements, resistance spot welds are required to be larger on thicker materials and smaller on thinner materials. The tool described provides a simple way of checking the diameter of spot welds based on the thickness of the material being welded.
2. Related Art
In arc welding processes the use of Fillet Weld Gages allows inspectors to easily determine if welds conform to specification by providing a tool to gage the profile of the weld. The device shown in TTL News Jan. 15, 2000 measures the arc of a weld that has been made when affixing sheets or bars in a continuous welding profile. This device is used to gauge continuous welds and not spot welds.
A tool to do the same with Resistance Spot Welds was identified, and this patent application is the result.
Resistance Spots Welds are normally measured with calipers in two directions around the weld nugget. As in arc welding processes the use of Fillet Weld Gages allows inspectors to easily determine if welds conform to specification by providing a tool to gage the profile of the weld. A tool to quickly provide weld size validation was needed to get acceptable results quickly and easily. The device disclosed allows simple checking of the weld nugget or spot weld without mathematical calculations. Previously, a Technician would use calipers to measure the diameter of a spot weld or weld nugget, record the number, and then take a second measurement 90 degrees from the first measurement and record the second number. These two values would then be added together and an average diameter would be obtained. The technician would then measure the thickness of the material being welded together. Once the material thickness was obtained, the Technician would then consult a chart or standard for the material thickness to see if the diameter of the spot weld or weld nugget falls within a given diameter range. If the spot weld or weld nugget diameter falls within the range given in the standard or specification, then the spot weld was acceptable. While standards are generally known in the art, individual manufacturers or customers can have individual standards or custom standards.
The tool described herein gages the governing material thickness by fitting the thinnest material into the smallest slot. The Technician slides the welded material into the slots until the smallest slot that the material fits in is identified. No actual measurements are necessary and hence little chance for error. Once the smallest slot is identified, the Technician looks to the weld hole corresponding to the identified slot. The weld hole identified is the minimum diameter that is acceptable according to the specification.
The adjacent weld hole represents the required spot weld or weld nugget size. If the weld nugget cannot fit into the adjacent hole, then it exceeds the minimum weld size for that material thickness and is acceptable. If the weld nugget is smaller than the weld hole, and the tool can move back and forth indicating that the weld nugget diameter is smaller than the weld hole, the weld nugget is smaller than the minimum diameter for the specification and the weld nugget is not acceptable. The tool disclosed does not require any measurements or math skills. The inspection can be done visually by using this tool. Technicians do not need to make notes about measurements, calculate an average diameter nor do they need to have specification sheets or learn how to use them. The margin from Technician error is significantly reduced with the use of this tool.
A first object of the present inventions is to provide an easy way to check weld nugget diameters based on the thickness of the material being welded.
A second object of the present invention is to provide a simplified method of checking the specifications of weld nuggets without needing math skills.
Another object of the present invention is to provide a tool that does not require the use of tables or charts to verify any measurements obtained.
Another object of the present invention is to provide a tool that allows visual and physical reference of the weld nugget in relationship to a custom or standard specification.
These together with other objects of this invention, along with various features of novelty which characterize this invention, are pointed out with particularity in the claims annexed hereto and forming a part of this disclosure. For a better understanding of this invention, its operating advantages and the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated a preferred embodiment of this version of the invention.